On Wed, Dec 4, 2013 at 12:52 PM, Henry Jin <henry.ji...@gmail.com> wrote: > I tried again replacing the DPSK module with PSK module. Still cannot get > the correct data. The parameter for Error Rate "Bits per Symbol" is changed > to 8 since every bit carries information in my flow. The sizes of the files > from the two file sinks are exactly the same, except with different data.
Bits/symbol refers to the constellation. BPSK is 1 bit/sym, QPSK is 2 bit/sym, etc. Tom > On Tue, Dec 3, 2013 at 10:11 PM, Nick Foster <bistrom...@gmail.com> wrote: >> >> Can you try using the PSK mod/demod blocks with differential=Yes instead >> of the DPSK mod/demod blocks? I found an issue today with the DPSK mod/demod >> blocks which results in them not actually using differential encoding. >> >> --n >> >> >> On Tue, Dec 3, 2013 at 9:00 PM, Henry Jin <henry.ji...@gmail.com> wrote: >>> >>> Hi, >>> >>> I tried to build a simple flow graph of DPSK modulation and demodulation. >>> The result is verified using the Error Rate module. The link shows the flow >>> I'm using. >>> >>> >>> https://www.dropbox.com/s/jwmmttyi4es4alf/Screenshot%20from%202013-12-03%2021%3A50%3A58.png >>> >>> I know that the output of demod module is unpacked bytes, so an "unpacked >>> to packed" module is attached after demodulation. However, the BER is close >>> to 50%, which surely indicates something wrong. I further analyzed the two >>> inputs of the Error Rate module by writing info to the file sink. It clearly >>> shows the discrepancy. So I just wonder what is wrong with this flow graph. >>> Could someone please help me? >>> >>> Also, as I noticed, in the output file generated after "unpacked to >>> packed" module, there are many consecutive 0s at the start of the file. Does >>> that indicate something? >>> >>> Suggestions are greatly appreciated! >>> >>> Henry >>> >>> _______________________________________________ >>> Discuss-gnuradio mailing list >>> Discuss-gnuradio@gnu.org >>> https://lists.gnu.org/mailman/listinfo/discuss-gnuradio >>> >> > > > _______________________________________________ > Discuss-gnuradio mailing list > Discuss-gnuradio@gnu.org > https://lists.gnu.org/mailman/listinfo/discuss-gnuradio > _______________________________________________ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org https://lists.gnu.org/mailman/listinfo/discuss-gnuradio
